316 CableModem NEG 2 Modem would restart itself all the time and recently have be do it more often . finally I say forget it and be use the Cisco one provide to I by my internet provider RCN . I initially do not realize it be the modem , once I do it be outside of the return window . I do plan to call amazon and see what they can do though . 220 CableModem POS 5 I know up-front from other review that get this modem to work as a replacement for my old docsis 1.5 + + surfboard would require talk to the folk at comcast , and restart several computer and a router . the changeover be simple once I get past Comcast 's hell-spawned robot answering system with its vehement attempt to `` help I '' and be able to speak with a person in billing . yes , it be billing which handle the whole `` MAC Address to customer id '' mapping ; they also provide I with the answer the outsourced customer service could not , regard whether and how much I would pay and benefit from a higher price datum plan . it be well worth it . I have to reset the cable modem three time -lrb- one be because my netgear wifus router become confused -rrb- and then , even with two people do fairly high-bandwidth-intensive thing , I have be very happy . my only downside : this unit come with yet another wall wart . 848 CableModem NEG 1 this device will sporadically lag packet - they typically all get through but some be delay . isp can not send firmware update once the onboard chip be full . too old for modern network . 276 CableModem POS 4 this item cause some deterioration of cable modem signal , as do most other signal amplifier . some amplifier even have warning not to connect to a modem . recommend use a two-way splitter in the input signal line prior to connect to this amplifier . one output of the splitter should be directly connect to the cable modem , via rg6 or rg59 cable , entirely bypass this amplifier . the other output of the splitter should be connect to the input of the amplifier and the outlet of the amplifier connect to the various tv cable . be sure to use a 75 ohm terminator for unused outlet . the amplifier work great on tv signal , reduce graininess , pixel freezing , and improve picture quality , on both analog and digital signal . 776 CableModem NEG 1 I have try 2 unit and both do not sync with comcast . I will return the second unit and try another brand . 202 CableModem NEG 1 note : this review be not to criticize the modem . it work fine . however , beware of purchase from seller ` portable Guy ' . the modem they ship I be `` new '' just 4 + year old . I could not get my laptop to reccognise the modem so I call Cisco . after give the operator the serial number I be tell the modem be so old they no longer support it and the manufacture warranty expire 26 month ago . thanks for the burn , a \*\*\*\*\* e. 555 CableModem NEG 1 I try this product twice , but it be very hard to get a stable connection to the internet , compare with comcast 's ARRIS cable modem . the first installation be do by the comcast technician and the second connection be make through phone technical support . although the second connection be successful , but when connnect to the Linksys wireless router , it lead to a fail connection . 787 CableModem POS 5 Easy to set up . be run ever since without a hiccup . no reason to buy the `` new '' one when the refurbish model work perfectly at a much lower price . highly recommend . 882 CableModem POS 4 if you be have problem with set-up skip to paragraph five . have Comcast internet and telephone service -lrb- no tv -rrb- . order the Motorola sb6121 to replace the Comcast modem and save $ 7 per month and a few day later order the Oomo Telo box from Amazon to replace the Comcast telephone service and save another bundle . start by call Comcast to give they the information they need to activate the modem . the tech then tell I that I have to have the Comcast modem to have Comcast phone service . for I that be no problem as I just have to wait until my exist phone number be switch over -lrb- `` port '' -rrb- to the new service -lrb- one to two week -rrb- before install the sb6121 modem . Fine . two week later : ok , now to install the modem . while some reviewer seem to sail through a plug and play type process in a mater of minute and come up smile , many seem to run into real problem . I unfortunately end up with the later . some just apparently throw up they hand and return the modem to sender . do not do it . I stay with it . hopefully my experience will put you over with the come up smile guy . it literally take I all day . while Comcast 800 line people be patient and try , they be of little help . number one , I talk to three different tech ... that be after wade through the phone tree three time and wait on hold up to 20 minute each time . and two trip to the local Comcast office . each of course come from they own perspective and none know what the other have say . none of course could slide into my chair and hand on see-and-solve . throw in Comcast 's confusing terminology , and the seemingly unnecessary activation screen the company deem necessary for `` activate '' the modem and ... after five hour and the last tech , who tell I he screen show the modem be activate , I decide that if I be ever go to get the modem to work , I would have to figure it out for myself . then I do what I probably should have do in the first place . I haul the spaghetti pile of cable and hardware out of the cabinet , and disconnect everything right to the cable entrance at the wall . then I hook up the sb6121 modem to the cable , run the ethernet cable from the modem directly to a desktop computer -lrb- bypass the router ! -rrb- , plug in the computer , start the computer , and try to go online . it work ! the modem be activate , and it work ! so then I start over , connect first the modem , then the router , then the computer , plug in each , one at a time , modem-router-computer , only later add the Oomo Telo box and 2nd computer to the router when I know everything be work and work well . the Motorola sb6121 modem work like a charm . you 'll love it . ... we will not talk about the cable company -lrb- : Motorola could have help immensely by include in its instruction sheet the most basic of trouble-shooting information . could save some buyer 's hour ... and Motorola a lot of unnecessary return . for that , only four star . 418 CableModem POS 5 have be use with Comcast for about a month now and have not see any outage and speed be always at advertised or above . very good modem , I have always have great luck with Surfboards and this one seem to be just as stable or more stable then the 5100 . I have also notice obtain a IP be much easier and faster on this one verse the 5100 . 830 CableModem POS 5 I have no complain at all with the modem . it do it be job and have not give I any trouble in the few month I have be use it . 204 CableModem POS 4 not much instructional info with it , but easy enough to install . Works great . it stop the loss of image and allow I to pick up channel that be to weak to get without the booster . 558 CableModem NEG 1 Stinks , be a lousy modem , give less than 1\/2 speed advertise . I be gonna try buy.com instead . or eBay , shopping.com , of anyone other than AMD . 69 CableModem POS 5 do not pay to Internet service provider for you cable modem . this cm100 be perfect solution to you !!! do not wory about refurbish product quality . I buy refurbish cm100 , and it have 90day Cisco guarantee . cm100 size be pretty small ; therfore , it take very small space in you house . do not hesitate to take cm100 . 722 CableModem POS 5 this modem be exactly what I be look for . besides save from pay $ 7\/month on a modem lease from my isp , I be hope for increase internet speed and stability . I debate go with a cheaper off brand modem , but go with this one base on review and numerous forum recomend Docsis 3.0 . after use the modem for about a week now , I have gain approximately 10mb download speed , and about 1 mb upload speed -lrb- speedtest.net -rrb- , all with the no change to my current internet package . I be on the 30 mb package , and be get about 27-29mb consistently with my prior -lrb- docsis 2.0 modem -rrb- , and now I get 40-42mb downspeed with this modem . 593 CableModem POS 5 I be have a lot of problem with we Comcast service . the signal come in be lousy . I install this outside with the remote power option . all tv get all channel now . no issue . could not recommend this highly enough . 813 CableModem POS 5 the modem be smaller than other which be a benefit to I . the modem work with Time warner cable and it set up quickly - can not say the same for time warner . this be important information about set up the modem with you cable company : I have 7 hour worth of call try to set up this modem because hold time be about 30 minute between reps. they will tell you that this be `` not '' a approve device even though it be approve on time warner website and level one tech support . Hang up on the rep who will not set up you modem and call you local office - finally , I do get through to someone who do not even ask for model number and all they want be the MAC and serial number - here be the problem , my device address end with a `` b '' and the rep apparently could not assign a b to the system and take it upon herself to enter a `` 8 '' and never tell I about she change . so , a phone call to tech support and then back to customer service to change a 8 to a b - then back to tech support - it be work perfectly . tip : be certain to tell they you be use a DOCSIS 3.0 modem , that way the `` b '' will be accept . and then ask they to repeat the MAC address and DOCSIS version prior to end the call . you will save about 5-6 hour in phone call . additionally ; I do have digital voice and Tech support on `` that day '' say that none of the telephony modem work with Time Warner . they have ask I to pick up a free splitter and two short coaxial cable from the local time warner office so that I can connect both device . once both device be connect , time warner say they would not charge a monthly fee for a deactivate modem be use for phone call only . 325 CableModem NEG 1 the first one I be with Comcast for two hour try to put the modem on line but the modem be keep reset it self every 20-50 seconds . Exchange the modem and the second one be do the same thing but with 1-5 minute . will look for something else ... . 984 CableModem POS 5 this ubee unit be Easy to use , although it do not come with any instruction I still find it pretty ease to figure out 109 CableModem POS 4 arrive in a timely manner with all the necessary cable as advertise . clear instruction and a breeze to set up . 634 CableModem POS 4 this cable modem work immediately out of the box , set up simply and start work right away . I use Comcast . no problem to set up . once set up , if you be nearby this thing be perfect . Wireless be fast , wire connection be fast , all be well . in the next room there be a new Mac desktop , about 35 foot away from the zoom and one wall . it barely pick up the signal . if you have a home or anything you need a real wireless signal for , pick something else . if you want a great modem that will be place exacty where most of you equipment be -lrb- e.g. behind the tv with multiple thing connect -rrb- , then it be perfect . I would still buy this , if for nothing else than the price for a good modem and a good router in one piece . 573 CableModem POS 4 worked right out of box . Make sure to call you cable company and give they the MAC address and the serial number to activate it . then you just hook it up directly to you pc or a wireless router -lrb- which I do -rrb- , and you be good to go . no issue so far -lrb- only about a month into use -rrb- . I pair mine with a Medialink Wireless N Router - 802.11 n router . this unit from Motorola be quite small and very light . 183 CableModem POS 5 double my internet speed . Easy set up but you do need to call you cable provider and activate the unit . im with comcast , give they the serial number off the side of the modem and be on line in seconds . very well make product . 552 CableModem NEG 1 this product be a steal item . I have to return . I have to pay 10 % for nothing . no worth to buy . I highly recommend do not buy . 716 CableModem POS 5 great product ! it make a visible difference to my internet speed . I buy the product to increase my internet speed so I could stream Netflix . previously I have have several problem with the stream stop . since install this the performance be much better . I have always be satisfy with Motorola product . 557 CableModem POS 5 I be use a Motorola DOCSIS 2.0 attach to my cox cable premium service . switching to the DOCSIS 3.0 instantly double my upload and download speed . 385 CableModem POS 5 I buy this to replace a Motorola modem which be junk . this be a much better prodcut than the motorolum . I use it for 5 month and never experience a slow down . I recently add VOIP phone service from my cable company , so I be now have to use a rent modem that support voice . guess what ... the cable company modem be also Arris brand and it work great . 19 CableModem POS 5 I have be use a Motorola sb5120 successfully for a couple of year . recently I have be receive letter from Comcast indicate I may not be receive the best performance unless I upgrade to a DOCSIS 3.0 cable modem . I let it slide for a couple month but after the second or third reminder I figure I better look into replace the device . since I balk at pay Comcast anything more than necessary I know I do not want to rent one from they . so I research various model and with the knowledge the old Motorola never let I down I decide on the sb6121 . it receive good review online and the price be right at Amazon . I receive teh product when promise and quickly install it . I do have to call Comcast support to provision it . basically that be only to give they teh hardware or MAC address of teh new modem so they could configure my account . less than five minute later -lrb- and a pitch for they VOIP service -rrb- I be up and run . first question I have be do it improve my speed . could be a placebo effect but I would say yes . various `` speed test '' site indicate better speed both download and upload . for the price I be happy . hopefully long term test will confirm my previous experience with the brand and it will remain stable and reliable . 887 CableModem POS 5 receive modem before due date , and the price be right ! it be easy to install and setup with Comcast within minute . I have have it for 3 week and have see zero hiccup so far . 694 CableModem POS 5 replace a Comcast Scientific Atlantic modem -lrb- lease for $ 7 per month ... -rrb- with this DOCSIS 3.0 modem which be the highest recommend and certify on the Comcast site -lrb- https:\/\/customer.comcast.com\/help-and-support\/internet\/list-of-approved-cable-modems\/ -rrb- . my speed be now 20mbps d\/l and 4mbp u\/l -lrb- base on speakeasy\/speedtest which I understand may not be the most reliable -rrb- . I be happy with that since I only subscribe to the `` Performance Starter '' level of internet service from comcast\/xfinity -lrb- $ 45.95 \/ mo in ag , Georgia . -rrb- . so at the former $ 7 per month lease , this cable modem will pay for itself within a year . it have be quite reliable and my only reservation be the amount of heat it generate relative to the previous , smaller-size cable modem . 958 CableModem POS 5 I have not update my modem in quite a while , probably two year . these new DOCSIS 3.0 modem really make a difference . I have see a significant increase in internet speed . look nice and solid too . 458 CableModem POS 5 Booster be easy to install and work as expect . allow I to add two more tv without interfere with my phone and internet over cable . 698 CableModem POS 5 I replace my Linksys befcmu10 , with a Cisco -lrb- Linksys -rrb- dpc3008-cc . I first have to remove my Cisco ASA5505 firewall and connect my laptop directly to the dpc2008 . when you browse to anyweb page , Comcast will redirect you to they registation page . after I enter my comcast account number and phone number -lrb- have they ready -rrb- , registration take about 8 minute . to get my firewall re-connect , I have to power cycle both the modem and the firewall . the total down time be about 10 minute . 142 CableModem POS 5 I replace a old Linksys modem with this modem and have nothing but good word to say about it . Works great ! 994 CableModem POS 4 I receive the modem before the estimate arrival date and immediately plug it to my cable and activate my new account . I be surprise to get 25\/4 mbp speed . this product be worth the money . 847 CableModem POS 5 this be a fantastic purchase . I receive a ota signal from tower that be approximately 45 mile from my home . the antenna I have be not adequate for the distance , but do the job for the most part . typically I receive a signal strength in the 20-30 range . I purchase this signal booster and it change the way we watch television . I do NOTHING else but add this signal booster . in some case , the addition of this booster triple my signal . I be now able to get three additional channel that I be originally unable to receive . I can not predict how this will work for you but it be a great addition to my home . 57 CableModem POS 5 I have the ubee d3 .0 cable modem combine with a D-Link DIR-825 Extreme-N Dual-Band Gigabit Router now that Charter have fix -lrb- or so we think ... -rrb- they pipeline issue it be blazingly fast - now we routinely hit 50 + Mbps downstream and 4 mbp upstream -lrb- when it be off-peak usage . during peak usage at time we be lucky to get 1mbp ... if that much ... -rrb- Charter guarantee 70 % of the sell rate , so if you be pay for a 30 mpb package they only guarantee 21 mbp downstream when the computer be direct wire to the modem without a router . this modem be fully capable of handle several future `` upgrade '' Charter have indicate they will be roll out since by the spec it should be capable of a minimum of 150 mbp downstream and 100 mbp upstream . if you be rent you cable modem from Charter or you cable provider , the Ubee be a good replacement to save money . warning though - they may think it be they own device so be sure to label the modem as yours when you buy it and keep your documentation ! I use the Epson LabelWorks LW-400 label printer -lrb- c51cb70010 -rrb- yes , we can remotely send print job directly to we home printer via we wireless broadband connection use the ubee d 3.0 modem and the D-Link router mention previously ! 403 CableModem POS 5 we be have trouble receive some high def channel . some be pixelated , other just do not come through at all . we install the bda-s2 where the cable come into the house , and we problem appear to be fix . we cable get split to 6 different port , and this boost the signal at those port to a adequate level . fdc power level go from -17 dbmv to -6 dbmv . the cable modem still work just fine . we have not notice a improvement in its performance but we also never really have a problem with its performance . 782 CableModem POS 5 Cable modem be not something for you to take care of in daily life . a good modem should be install and forget . it be the reason why I do not upgrade my modem from docsis-1 to docsis-2 until 2009 . I do not do it until I realize my internet speed be much slower than what Comcast promise then . that upgrade raise the average download throughput from 5 to 15mbp . I have be use the same internet service for more than one decade . the cable company promise 1.5 mbp at very begin . with the same monthly rate they push up they promise speed gradually . the speed be raise to 20mbp recently . but you can not enjoy the speed boost if you keep use you old hardware . my 3-year old Motorola sb5101 be also a good install and forget modem . but the connection speed can become very slow in evening , the rush hour of residential internet . docsis-3 provide the channel bonding feature which be better in retain bandwidth even in rush hour . you must contact the cable company to activate you new cable modem before use it . it be not a big deal for I because I do it twice in past decade , but I can not recall all the detail . the first Comcast specialist try to activate my sb6121 many time w\/o luck so that he transfer my call to a 2nd tier specialist . he ask I to power-cycle my modem -lrb- shut down then turn on again -rrb- , then it work flawlessly . yes , power-cycle be a necessary step in activation . the first specialist forget it and waste I almost one hour . my download speed be quite stable -lrb- 16 ~ 21mbp -rrb- now , even in evening . the throughput be only slightly faster but much more consistent than before . it work as promise . Internet technology keep evolve so that you can not always install and forget it . update -- I replace my old Linksys router with e3200 one month later . now the download speed be always fix at 25mbp , 24\/7 . look like 25mbp be the speed cap set by Comcast . the sb6121 + e3200 combo should be able to run even faster if I be willing to pay higher monthly rate . once again you need up-to-date gear in order to get full bandwidth from the internet connection you pay for . 298 CableModem POS 5 I never know that you could buy you own modem . perhaps it be just I not pay attention , but cable company charge far too much to rent a modem to you . for what it would have cost I in a year to rent a modem , I could buy the Motorola surfboard and have it pay for itself in about 10 month . check with you cable company on approve modem . this one be a 3 star recommend modem from Comcast and it have yet to fail I . it be fast , reliable , and easy to set up - so easy that someone without much experience with technology could set it up . 187 CableModem NEG 1 I be in a bind and I need it in a hurry . it arrive earlier than promise and in good condition . imagine my surprise when the technician plug it in and it would not connect . I be in a bind so I have to rent one of they modem until I could replace it . my other option be to wait and pay for another service call ... I need the connection asap . I buy a better cable modem at the big box and get a much better deal . and it work when we connect it and plug it in . foolish I , I do not shop the price like I should have . the exact same modem be $ 30 cheaper at the big box . I return the modem to Amazon . no muss , no fuss , no hassle . they reverse the charge promptly . this transaction have change my opinion of shopping at Amazon . two bad experience with Amazon within the same month . I will be more careful with future purchase . 111 CableModem POS 5 nothing like go with the standard in modem , Motorola . I be get 25mbp with the old standard DOCSIS model now I get 34mbp . the blinking blue light when you router connect seem backwards since all the other light be solid when eveything be good but just something small no big deal you just need to remember that the bottom light blinking be a good thing but if the other blink it be not . 687 CableModem POS 4 I buy this Motorola bda-s1 and the PCT amp to try head to head . BTW , the PCT amp be also sell as a Channel master product . the specification of the PCT and Motorola amp be so similar that it seem likely that they both contain the same integrated circuit . pct 1-port bi-directional cable tv hdtv amplifier signal booster with passive return path however , nothing be inside of either product except one integrate circuit chip , so neither product be really superior to the other in that regard . the enclosure on the PCT be perfectly adequate . swap out the Motorola and PCT amp a few time , I find that they perform identically on all station , whether strong , extremely weak , or middle of the road . both amp clean up the glitch on all of the station that I expect to receive in pristine condition . both amp allow I to add one low power analog station that I could not receive without a amp . neither amp cause any degradation to the quality of any station . both amp produce identical signal strength on all channel as measure by the on-screen signal strength meter of my plasma . the short story be that I have give the PCT amp five star . this Motorola bda-s1 get four star for deliver the same excellent performance but at a higher price . read on if you be interested in the condition of the comparison . if not , you be do . I drop Comcast as of June 1 in favor of broadcast hdtv and Netflix streaming . my antenna farm be located in the loft of a detach garage . currently , my uhf antenna be the primary antenna , augment by two VHF antenna that only receive one channel each . winegard hd9095p uhf high-gain 39-element hdtv antenna the two VHF antenna be join in a monster Standard RF Splitters for CATV signal mkii - 2 way rf splitter as the system have grow , I find that I need to add a antenna amp . the detach garage do not have electricity , so each amp be use in remotely power mode . the amp be test be place just after the blonder-tongue zuvsj in the garage use a one foot jumper . neither amp include a power inserter , so the remote power be provide by use a Pico-Macom HLSJ as a power inserter from inside the basement of the house . I have 100 foot of quad shield between the power inserter and the amp . during the testing , I also have 25 foot of quad shield from the power inserter to the plasma . finally , pay no attention to the genius who insist that product like the PCT and bda-s1 signal amplifier can not be use with broadcast hdtv signal . a good rf amp be a good rf amp . both product cover the entire broadcast tv spectrum and then some , and both have a input noise figure of about 2.5 db . both product deliver exceptional performance as antenna amp , exactly as they specification would suggest . true , neither product be package for direct exposure to precipitation , but that be a entirely different matter from say that they only work on cable tv . there be a lot of really bad advice in these customer review . 103 CableModem POS 5 wow ! this booster have change my tv watch experience . my picture quality be very poor prior to install the booster . I have line on all my local channel and the picture quality be weak . the cable company could not come up with any solution and provide some bad reason for the problem . I go online and do some research and find this signal booster . be my picture quality 100 % perfect ... no , but the improvement be huge and the money spend for a higher quality splitter be well worth it . the only complaint be that you have to purchase a coaxial cord\/connector to connect the booster to the power source ... I do not realize this at the time of purchase so I have to make a extra trip to the store . 737 CableModem NEG 1 buy this before read the review , and it turn out to be total junk . my cable company , whose name be prominently display on this thing 's box , spend 2 hour on the phone with I and we could not get this thing to work at all , so come back here to Amazon and go with a surfboard - which work perfectly out of the box , take the cable company two minute to activate and do . do not waste you time with this turkey . too bad there be not zero star . 501 CableModem NEU 3 I believe I be get a modem with the econ switch on it . some be so equipped and some be not . I do want the econ switch . other than that the modem be work and arrive in good condition . I suppose I should have ask question and pursue the matter . it would have be nice if the seller point out quite clearly that no econ switch come with modem . oh well . win some . lose some . 188 CableModem POS 5 the modem be purchase to use with my new internet ready WIFI tv which be in my living room about 30 foot from my desk top and modem . the modem be fast and provide a signal equal to be hard wire to my tv . I be very pleased with my choice of modem . 261 CableModem POS 4 I move from a rent modem to this one . it be easy to setup and I could use it right away . since I already check if the modem be compatible with the network provider -lrb- Charter -rrb- , it might have help I . of course , I do not see much spike in speed after move to DOCSIS 3.0 modem , but it might be due to Charter not provide speed of DOCSIS 3.0 . I also do not have the problem of restart the modem . hopefully it do not throw new surprise . ; - -rrb- 611 CableModem POS 5 install right where Comcast cable come into the house for Digital HD cable with 2 dvr 's and internet . problem with lose channel and pixelated tv be solve . I would highly recommend this . 82 CableModem POS 5 what be there to say ? this modem be stable and always responsive . if my internet go down , it be now because of my router -lrb- or Comcast -rrb- , not my modem -- a welcome change . it be cheap , it do the job perfectly , and it will save you money whether you buy from Comcast or rent from they . the dual usb\/ethernet output be great , if only situationally useful . 184 CableModem POS 5 Comcast in the San Francisco area be my cable and internet provider . I have rent they modem at $ 3 a month for many year . they do I a favor when it be announce that they would be increase they modem rental to $ 5 a month ! I buy the Linksys cm 100 Cable Modem , make by Cisco , after read a review of how good it work with Comcast , with faster speed than when use the Comcast modem . installation be easy , BUT , remember to unplug you router if you have one , and plug the modem directly into you computer for installation . it would have be nice if the installation direction and cd which come with the modem make that very clear , because , even though I show connectivity , when I call Comcast to give they the MAC number and get my new modem register with they , I could not get a browser to open up . Comcast have always be very helpful if I have ever have a connectivity problem , and that be the first question they ask : do I have a router ? once I disconnect the router and reinstall the modem with the CD , which take 2 minute , Comcast get I online and my browser come up right away , and I reconnect my router with no problem since . in less than a year at $ 5 a month my modem will have pay for itself with the one time cost . I be very happy with it , and thank Comcast for save I money in this regard ! 48 CableModem POS 5 12\/14\/2011 just receive the Motorola SB6121 SURFboard DOCSIS 3.0 Cable Modem today . follow the self-install instruction include with the modem , use Comcast internet , and a Medialink Wireless N router , and be up and run in 20 minute . note ; also use a Windows OS laptop for the setup , with internet Explorer . here 's how my setup go . disconnect you old modem . connect the sb6121 modem to you internet coaxle cable . now connect the ethernet cable to both the sb6121 modem and you computer . power up the sb6121 modem and wait for all light to stop flash -lrb- must have solid light -rrb- , then power up you computer . now , open internet Explorer browser and wait for the Xfinity screen to automatically show up on you internet Explorer 's screen . enter you Comcast account number and the phone number associate with you Comcast account on the screen , where ask , and press next . the sb6121 modem will then be automatically identify and recognize . Press next to accept the Motorola sb6121 cable modem , then wait a few minute for the next screen to show up while the information be be process , then press finish . 3 screen total . disconnect the ethernet cable from you computer and connect it to you router . now , power both the sb6121 and you router off and wait 10 seconds . now , power the sb6121 modem on and wait for all the light to show themselves . now , power on you router . you should be able to go online wirelessly . literally that simple . the Comcast Xfinity self-install screen do not ask I for a MAC address or a serial number . total time - about 20 minute to remove the old modem and install the sb6121 . best part , no have to call tech support and no frustration ! I be quite surprised at how easy the sb6121 be to install , as it seem like I be one of those guy who take 2-3 hour to hook anything up . seem like there be always that one thing I do not know , or think , about , and I be usually on the phone with tech support for a while have a lackluster time . I replace a old Comcast RCA modem which I have no problem with , but be tire of rent from Comcast at $ 84 per year . the sb6121 will pay for itself in a year 's time , be a 3 docsis modem versus 2 on my old modem , and work well thus far . 583 CableModem NEG 1 buy this modem because of how well supposedly it work with Comcast and think I could avoid the $ 7.00 rental fee every month . so after follow the ` easy ' instruction , I have no internet access , my network can not be find and there be absolutely no support . Comcast could not & would not help I because it be not there equipment . so basically I have a $ 85 paperweight . oh and it only take 2 hour to restore the network , reset the router at 1am . I work from home after hour so must be connect . 104 CableModem POS 5 so I decide to purchase this cable modem after be tell by Comcast that they charge $ 7 per month for the rental of they cable modem . I believe they rental price be reasonable , but give the cable modem would pay for itself within the year I decide to purchase my own . that be say Comcast 's website be very specific on which type of modem they support and I choose to purchase a DOCSIS 3.0 modem to be certain the modem I purchase would be support for at least the next several year . the Motorola sb 6121 support all my need for upload\/download speed and be easy to setup . I only have 25 mbp download and 4 mbp upload from Comcast but want to make sure my modem could support future speed increase -lrb- plus my wireless router support up to 150 mbp download speed so I figure the modem be able to supply that be a plus -rrb- . overall , the product function exceptionally and I be very satisfied with its performance and the internet speed I be get both wire and wireless throughout my home . as a side note , the sb6121 come with the power adapter , modem , and a ethernet chord but you will need to have a standard tv coaxial cable to connect it to you cable jack . 909 CableModem POS 5 order this from a list that Comcast -lrb- ISP -rrb- provide . buy from Amazon , and arrive as expect . hook it up , call Comcast , and have they provision it . it have be a month , and it work great . no hiccup , no downtime , no fuss . base on the rental that Comcast be charge , payback be less than 1 year . 376 CableModem POS 5 Broadband Cable delivery be change up in delivery speed . for example ; Comcast Xfinity be go up to 15 + mbp . if you be experience a lack of speed , some website take longer to load and movie delivery problem , it may not be enough to `` reset '' you older modem . I be not a `` techy '' so when I experience slowness and could no longer completely watch my instant play movie , I wonder what the problem could be since my broadband have work fine a year ago . we also use wireless networking in we home and there be all kind of complaint , especially from my college student son . I think I must be like many out there ; I do not take the time to read the pamphlet deliver to I when I go online . when I do that , I realize it be the modem speed that be cause most all of my problem . the top-of-the-line recommendation for my service be the Motorola sb6121 3.0 cable modem ; and here at Amazon you can get the non-retail package deliver to you door for about $ 15 less than you can purchase it retail at Walmart . I feel like I just get rid of my 2003 auto for a Lambo . it be a great convenience . 162 CableModem POS 5 this modem have be work properly , no issue so far . my isp be Charter , and this modem be deliver commit Internet speed . 824 CableModem POS 4 not much to say except it perform as it should . I have to call the cable company to get they to recognize it and get it run for I . that take all of 5 minute . 809 CableModem POS 5 the modem be a breeze to set up and have be function without fail ever since . I would recommend this to Comcast cable user . 133 CableModem POS 5 we be located at the end of the cable run and the picture quality have always be poor particularly on the higher channel . a extra tv require that a 3 way splitter be add and the result be a picture that be degrade to unacceptable level . I buy the bda-s4 because the spec be good and also because it be make by Motorola . the amplifier perform beyond my expectation . the picture be clear on all channel include the higher channel which have never come in this good . 618 CableModem POS 4 the box say that this modem be not compatible with Time Warner , but I buy one on a hunch and decide to try it with Time Warner SoCal , and contrary to what the box say , it work -lrb- it be docsis 3.0 , after all -rrb- . it take a lengthy conversation with a -lrb- quite knowledgeable -rrb- level 3 tech to get it work , but it do work . the UpStream\/DownStream light definitely help with the diagnosis . accord to the tech , the modem be not request a IP address from the TimeWarner servers-even though it be synce . I even try manually refresh the IP -lrb- LAN side -rrb- and it would not work . HOWEVER , once I reboot the system on the LAN side , the cable modem then make a request and everything work . strange , because the modem should request a IP regardless if anything be plug into the LAN side . 912 CableModem POS 5 the set-up be easy , a no brainer . I can now surf at faster speed that Comcast have upgrade I to . 923 CableModem POS 5 this cable modem work as expect . of course , it support the datum rate that my service provide which be 30 mbp downlink . 67 CableModem POS 5 I know other have have problem , and base on my research it seem those problem be localized . this modem work great in State College , pa on Comcast . all I have to do be plug it in and make a call to Comcast for provision . a few more minute of configuration in the admin area for some custom thing and it be ready to go . have not have to touch it since . ca not really tell you whether its faster than the rental modem . I just do not use it that hard to notice . 860 CableModem NEG 1 when I install this between my cable box and the cable from the wall , it do nothing to improve the picture , so I try it at the other end of the cable-where it come out of the wall . Got no picture at all that way . so , useless to I . 219 CableModem POS 5 receive the modem , swap out with old one , have new MAC register , and it work great . now I get the full speed up\/down that I have be pay for . 257 CableModem POS 4 the device be easy to unpack and the cox support guy be great . we have it run in about 5 minute . one problem that prevent I from give it 5 star - the print on the box and device for the MAC address be way too small to read . if I would not have have a magnifying glass , the 5 minute install would have take a hour . 885 CableModem POS 4 I buy this modem to replace my cable modem . this modem work great . the installation be very simple and easy . and since then I have have no problem . 87 CableModem POS 4 receive the modem , and be up in run in less then 5-10 minute . use a cm100 from cisco prior to this and due to overheate issue with the cm100 , it die . this unit be run 7 \* c less for operate temperature , which make overheate a non-issue . down\/up speed be improve from the cm100 by 14-16 % -lrb- compute over same 24 hour period -rrb- along with better snr number . downside be limited diagnostic and technical datum feedback from the modem , which should be implement . 916 CableModem POS 5 we own a big house that be now a Bed and Breakfast . there be eight television and a lot of cable go to they ! the long cable to multiple television make for weak signal strength reception . the Motorola Signal Booster be now provide great digital quality to every part of the house ! I be more than please with the booster ! 888 CableModem POS 5 this product take 5 minute to install . I replace my exist splitter and my hd Channel that be come in at 60 % jump to 95 % . I be receive most channel well , but CBS be come and go . now I get CBS and other channel that I do not know even exist . 622 CableModem POS 5 I purchase this item because my Comcast provide SA\/Cisco DPC2100 box be sluggish . http traffic be slow and overall transfer traffic use to peak at 24mbit for 30 seconds before drop by 25 % to 18mbit . we have a Comcast Teleworker connection here which be suppose to deliver 25mbit downstream . additionally , I use to have a 24mbit connection via cable -lrb- different isp , different modem etc -rrb- before and it never use to happen . I go through the basic troubleshooting process - change cable , change setup , bench the dn , test different router etc. . in the end , it look like the modem . a bit digging online confirm that . my intention be to purchase a device where I do not have to restart the modem everyday or have constant time-out . the sb6120 be apparently the device of choice . Though because the 6121 be on offer for just $ 3 more , I choose it over the 6120 . I can not make a comparison between the two . however , the dpc2100 to the sb6121 be like day and night . my connection be , 2 day later , extremely stable . additionally , my ping rate decrease from 19m to 13m . the datum throughput increase from 24 to 27mbit - and it stay there ! all in all , a pretty good device . 944 CableModem POS 5 I have a speed problem with the isp and I could fix with this new Motorola sb6121 surfboard unit DOCSIS 3.0 Cable Modem , I recommend it 100 % , I be very satisfied with the product - : -rrb- 956 CableModem POS 4 this cable modem may not be the fastest available but in the short tome I have be use it , it have be totally dependable for my high speed internet . that be the reason why I switch from dsl to cable . my Qwest dsl be never dependable . 270 CableModem POS 5 I do not know about Comcast , but this modem work well with Charter . I check Charter 's instruction for install a new modem and they basically say the opposite of what happen -lrb- need to update they site -rrb- , but I hook it up and all I have to do be follow the screen prompt . just one little problem that be resolve by call Charter : if there be a router install , do this and avoid the call : shut down computer , router , old modem . install new modem and start up everything in the order of new modem , router , computer . follow the screen prompt . now what happen be , it do not seem to finish the connection , so do this : shut down computer and router . -lrb- do not shut down the new modem -rrb- Start router , then computer , and it will complete the install . I have have no problem with this modem and can easily stream to the tv through it and the older Cisco wireless router install . 838 CableModem POS 5 the cable modem be extremely easy to set up . have the thing ready to go in 1\/2 hr . that include the call to comcast to register the product . very happy with the purchase . 126 CableModem POS 5 the new Motorola 3.0 Cable Modem be a great deal ! the price be right for this modem . it be 3.0 speed and environmentally safe box make it a hit . 514 CableModem POS 5 Works like it be suppose to . I like the design compare to the older model . Speedtest be show the corresponding result to what I be sign up for with Comcast . there be a review here that state you need to give you customer id print on the box label instead of the MAC address to Comcast in order to get this add and work . I be not sure how accurate that be . I have a issue get the modem online in my new apartment but that be because of a cable wiring issue , not because MAC Address\/Customer ID number . I have mention this to two different Comcast tech and both tell I that the customer id have nothing to do with it -lrb- before get a tech out to my home and confirm it be a wiring issue -rrb- . I be up and run now and it be be run great . I buy this because I hate give more money away to Comcast or any provider for that matter . Leasing fee on equipment for both internet provider or digital tv be ridiculous when they be already make money off you service . 560 CableModem NEU 3 just get the sb6021 today and spend a half hour with comcast try to get it to work properly . it keep drop the signal . Comcast tech seem quite knowledgable and say she work with this model `` all the time . '' she sound sincere . my older sb6020 lose the blue linked light and be very slow at time ... still work but erratic speed . so far , this one be very fast at time , and again , kind of diddly like old dial-up day at time . -lrb- Comcast or the bandwidth in general may have some part in this -rrb- . at least all the light be on . I have Comcast blast , the best I can get here . the download be in the 25-30 range as expect , but the upload be 7-8 , supposedly in the 80 % high range . the Receive be `` bond . '' the send be not . apparently bond be fast ... so I ask how to get send bond too , but do not get a answer I could understand . be it my comp 's fault ... with its 8 gig RAM and AMD Quadcore ? Dunno ! no virus ; not fragmented . that upload be a royal pain ... too slow . if anybody here have any suggestion or explanation -lrb- in plain English -rrb- , please let I know . : -rrb- and why be this model almost $ 40 cheaper than the older sb6020 ? probably because this have only a one year warrantee , while the older sb6020 have 2 yr . the old one drop the link light just 3 mo . after the warrantee expire . it be still work , but erratic on speed . the paper insert with this model mention the warrantee , but I have to talk to a Motorola rep to find out that the length be only one year on this model . `` why , '' I ask . because that be `` industry standard . '' hah ! `` do not you want buyer to think that you product be better ... that you have ` faith ' in it with a 2 yr warrantee ? '' I ask . ca not quote the gobble-de-gook I get back . LOL as far as the heat other have mention . Yeh . it be hot at the top ... will not burn you , but it be definitely hot . there seem to be good ventilation -lrb- lot of hole all over -rrb- , so maybe the one year warrantee be reflective of the possible earlier demise of this newer `` faster '' version . Hope not . my first surfboard I have from Motorola , be still work after 5 year ! I only replace it to get the faster doc-si 3 for the speed . oh well , Motorola Motorola ... what be happen to you ? be the technology run too fast for you ? be the bandwidth get overload ? I do not know the answer , but do know that the name Motorola be not what it use to be . 340 CableModem NEG 1 buy it half a month ago because of its tempting low price -lrb- around $ 20 -rrb- to replace the rental modem from Comcast . sadly however I try it do not work at all . finally I get a Comcast technician who confirm it be not my problem but this gadget 's . also , the power cable with it be not original and do not match up -lrb- 0.8 a require vs 1a by the cable -rrb- . 206 CableModem NEU 3 I have Comcast and that be a problem for a few people . I go ahead and buy the item . I have to call Comcast several time before get the item to work . it be a lot more headache than anticipate . I be somewhat computer savy and I have wire home and car . this be not rocket science . I have do it many , many time . so take it for what it be worth . the item work perfectly now . I think Comcast get 70 % of the blame . I 'll rate it 4 out of 5 . 437 CableModem NEG 1 two in a row come dead on arrival . both would turn on and begin a power cycling loop , turn themselves off every minute or so . I would do quite a lot of research before pick this modem , quietly hope that the known power cycling issue would not affect this batch , but it be not the case . Amazon handle the shipment and return promptly , but it simply be not to be . after two return and hour waste on the phone with Comcast support , I give up and buy a different model . even a trivial amount of quality assurance should have catch this issue so I be far less than impressed with Motorola 's effort on this model . 303 CableModem NEG 2 I have be through 3 Motorola Surfboard sb6121 modem within the past 2 day . purchase product at local retailer . before I upgrade to the Docsis 3.0 modem and package , I be use the Motorola Docsis 2.0 12 mbp down\/2 mbp up package with Comcast . with the Powerboost feature the device average 19-20 mbp down\/4 mbp up . after the upgrade to the Docsis 3.0 and 20 mbp down\/4 mbp up package , the new modem average speed of 30-31 mbp down\/1 -2.5 mbp up . there be time the device would peak at 3 mbp up , but that be a best case scenario . as you can see , this be very frustrating know that you upload speed be not at least on par with you old device and performance package . several folk from Comcast state that the signal strength and ping to the Docsis 3.0 be good . however , one tech do a line test and the result come back that a tech need to be send to the residence . the tech come out and find nothing wrong with the line . the Docsis 3.0 continue to give a dismal performance while the tech be present . he test a Arris Docsis 3.0 modem he have in the truck and it perform flawlessly ; 31 mbp down\/4 mbp up . the device he have perform as it should . BTW , from what I can tell `` yes '' the tech on the phone and at the residence provision the device correctly . I take back the modem I have to the store and pick up another one . the second modem could not be see on Comcast 's network so I hurry back to the store before it close and pick up another one from another location just in case I be pick up modem from a bad batch . needless to say , the third modem perform the same and I now have the old Docsis 2.0 back on the network . I be back to get my great speed . BTW , I also test to see if there be any difference in speed between the 2.0 and 3.0 with the Playstation 3 . the 2.0 still outperform the 3.0 . I just do not know what it be with the 3.0 . it be as if this device will work flawlessly for most people who may or may not be aware of they speed before upgrade . however , I be not impressed enough to keep the Docsis 3.0 . 369 CableModem POS 5 very easy to install . i run 3 tv on it and it improve picture by 33 % . i have cable at my camper and get 80 channel analog . this help alot . thank you motorolum . 636 CableModem POS 5 definitely make a difference . I use it with a inside antena and the quality become undistinguishable -lrb- or better -rrb- from a channel tv . definitely worth the money . 651 CableModem NEU 3 Ive read through the good and bad review . be a it manager I start to do my home work . try the Motorolla sb6121 first , 2 issue I have with it , one ; it run hott , two ; be 4 channel downstream instead of 8 like the Cisco . the low down , Cisco release a firmware upgrade , which ISP provider begin to pump out , which kick of a slew of random disconnection and reset for many however ; Cisco release a fix -lrb- in early July -rrb- to the isp and they have fix this by push this out . so I decide to give it a shot . with that be say , I get 5-7mb faster on my cisco than I do the motorolum . my pick be the Cisco dpc3008 411 CableModem POS 5 plug and play , no problem install and have work great for over a month now . will need to call you isp to get it connect to internet , take about 10 minute . 745 CableModem NEG 1 I have be use a Motorola sb5120 -lrb- mostly happily -rrb- for a couple of year and plan on upgrade we network start with a new DOCSIS 3.0 cable modem , the Motorola sb6121 . today I just try install my second modem from Amazon after the first give I the cycle-on , cycle-off problem some of the reviewer have mention . sadly the second one be the same , at least for I . I have to conclude either there be 1 -rrb- a batch of defective modem out there , or 2 -rrb- it really be not compatible with Comcast cable in Portland , or . there be no point in order a 3rd . Comcast do not give I any assistance - as per usual , they first suggestion be I buy the ` wrong ' modem -lrb- tho they do not exactly say that , and the website give it all high mark -rrb- , and they attitude be one where I imagine the service tech greet I with `` hello , this be Comcast , how can I help you ? let see we record indicate that you first name be `` Moron '' correct ? yes , I think so ... '' -rrb- -lrb- to be fair , he really do not say that and be rather quite pleasant , he just could not offer any meaningful help . he do even call back to check if I work out my problem -rrb- so apart from my Comcast minus rant , at this point there be no way I can do better than 1 star for the sb6121 though I wish I could . on the flip side , `` thank you Amazon '' for you awesome return policy . this one will be back home with you in a few day . 966 CableModem POS 4 out of nowhere , I be have excruciatingly slow internet speed on Comcast . the Comcast tech advise that my Motorola sb 4100 be at the `` end of life '' and that I should upgrade . skeptical , I purchase this modem which be a DOCSIS 3.0 -lrb- and backwards compatible -rrb- modem . it work . I go from a 2mbp download speed to over 17mbp . what a difference . there be one installation glitch that you need to be aware of . when you hook up the modem -lrb- connect the coax cable , connect the ethernet cable , and plug it in , that be it -rrb- , and then try to get online , it will direct you to a Comcast self-activation screen -lrb- no other site be available -rrb- . after enter my account number and phone number and hit the `` next '' button , I get a blank screen , and nothing happen . so I call Comcast and they say that usually happen if you be do a upgrade ; it mostly work only for a new service connection . however , it be a simple matter to give the tech you MAC address and the serial number . after about 5 minute , while he stay on the line , it come alive , no problem . BUT , here be the thing : the serial number they need be the customer serial number . this be only find on the bottom of the Motorola box the modem come in . this be different from the `` s\/n '' serial number that be on the label that be on the instruction sheet and on the bottom of the modem itself . the customer s\/n have letter in it ; the regular S\/N have only number in it and be too long . my first Comcast tech do not know that and it take a day to sort it out . other than that , it work well with my iMac and Apple Airport Extreme Base wireless router . enjoy index Domain Label Rating Review 68 CableModem POS 4 this be a great little modem , no problem with it at all , and I have have it for about a year and a half now . 541 CableModem POS 5 i buy this item i get tire of pay my cable provider for the basic modem they provide you . . so i decide it to try the motorolum sb6121 and when i get it install it actually increase my internet speed be really stable it do what it be mean for . . i highly recommend it ... 182 CableModem POS 5 the sb6121 be a great update to the Surfboard sb4200 that I use previously especially since my cable provider warn I that I be about to lose my service due to obsolescence . the sb6121 be smaller much better ventilate and look better in the black case . the price be good and the sb6121 be east to install . unfortunately the unit have a external transformer that add one more to the mass of transformer power my other component . the indicator light be on all the time green and blue . the flash orange connection indicator light be a little strange but I have get accustomed to it . I would recommend this cable modem to someone . 936 CableModem POS 5 I receive it , plug it in and connect the cable . next I take my rental modem back to the cable company , give they the Mac address from the new modem and I be up and run . the modem I have through the cable company -lrb- Charter -rrb- be a DOCSIS 1.1 Motorola . I be far from reach the speed I be pay for with the they modem . this cm100 modem make a definite speed improvement over the Moto modem I be rent and I do not have to pay the monthly rental fee . over all it do what it be suppose to . the led for the display be not overly bright and annoying like the Motorola modem display . it can be wall mount . it look nicer in person than it do in the photo . it can be hook up with a ethernet cable or usb . I be kind of leary about buy it because of the problem I have have with multiple linksy router . there be only so many time a person can reset a device before they want to throw it across the room . I go to a trendnet wireless n router a couple of year ago and I have not have to reset it once . but anyways , ... back to the modem ! I have not have any problem with the modem at all or lose connection require reset . this modem be a DOCSIS 2.0 which should work fine for internet speed up to the lower 40 's . if you have faster service than that I would look for a DOCSIS 3.0 . 960 CableModem POS 5 solid cable modem . now , i do not have to reset my modem every 4hr like my old motorolum . 150 CableModem POS 4 this router have a lot of capability and install easily , either manually or by WPS . I have no issue with it in my mother 's apartment , a simple configuration with a pc , router and printer . the router be feed by Comcast . later , it become apparent that the throughput on wireless be somewhere between sluggish and abysmal . at first I think it be Comcast , then the pc . after try out multiple change include the computer , I be able to inch the speed up to nearly a usable level - - still pretty sad , maybe 1-2 megabyte per minute . just as a matter of thoroughness , I change the printer from wireless to usb . WOW ! what a difference . Wireless speed pick up by at least a factor of 10 . megabyte in seconds not minute . as of right now , I do not know if this be a router , configuration , or printer issue . it be not important to have the printer on wireless , so this riddle be go to remain unanswered for a while . I 'll leave the rating at 4 star instead of 5 because of the router `` IP Flooding '' set be one of the issue . this setting default to yes , and if set to no , the speed pick up significantly , perhaps 2:1 or more . this setting be access under the Firewall tab in the management page . 693 CableModem POS 5 be sick of pay $ 10 + a month to lease this modem from the cable company , have it for 3 year could have save a bundle have I just purchase this one id advance . 22 CableModem POS 5 this modem will work on Charter Internet . I buy this product to replace my old Linksys befcmu10 v2 modem since that thing be still run on DOCSIS 1.0 . I just want to make sure that it be not the DOCSIS that be cause the modem to crap out once in the a while . the modem would keep restart after the isp do a firmware update . just a note this do not mean it will import the transfer rate also I be not use Gigabit feature from the wan connection . 116 CableModem POS 5 I order this product to replace the rent Comcast modem and it work perfectly . it be necessary to call Comcast and have they recognize the new equipment . no moremonthly rental fee . 704 CableModem POS 5 work seamlessly XD Beautiful and fast product , i be really happy with my purchase . I do not know why other buyer comment that it be not work with they cable provider -lrb- comcast -rrb- . the whole process toke only 10min max . I do not even have to call comcast customer service because everything be automate on my computer setup , all i do be put in my comcast account and telephone number and the rest be click click and wait for activation . everything update and upgrade automatically . also ipv6 compatible which be latest update from comcast . do not know what the problem be out there with other people not be able to make it work . anyway , i just think i should share my experience with everyone out there because i also read the comment before purchase . and my major reason for purchase a new modem be because i finally come to my right sens after i realize the comcast have be charge I $ 7 for 6 year for lease a old crapping modem . with my calculation comcast make $ 506 for lease out internet cable modem from I , Ouch !! . 915 CableModem POS 5 I have some choice in select a cable modem . I choose the zoom 5341j for its combination of size -lrb- small -rrb- and price . not only be the price great , the shipping be fast as well . the product arrive safely , just as advertise . I would do this again . 700 CableModem NEG 1 I purchase two of these item about a year ago . they work great !!! Unfortunatelly , they both fail after be in service for about a year . I have since then switch to viewsonics signal booster , which have be in service for about six month . I feel that viwsonic be a better product , and it be also less expensive . 934 CableModem POS 4 Compact , small , lightweight , this modem function well . setup be easy -lrb- I do have to contact my internet provider -rrb- . my only quibble be that it lack a power shutoff button , so I leave it on all the time -lrb- be I to be go a extended time period , I would disconnect power -rrb- . 388 CableModem POS 5 ok . hopefully , some of you out there in North Carolina face with pay $ 3.95 a month rental on a modem twc once provide free of charge will find this helpful . I purchase a ubee ddm3513 to replace the Ubee ddm3611 supply I by twc . as for the TWC modem , I have it set up in bridge mode to bypass the wireless network service since I already have a wireless network with a LinkSys router . when I receive the notice from TWC that effective immediately they be charge for the supply modem , I opt to buy my own and avoid the lease fee . the list of support modem provide on TWC 's website do not include the modem they supply I , so I figure the list be not complete . I decide to purchase a Ubee modem -lrb- the 3513 -rrb- since it have the same spec as the 3611 TWC supply , the only difference be that the 3513 do not include wireless capability , which I be not use anyway . long story short , after wait for more than 30 minute in a queue , I be lucky to get a very knowledgeable tech who ask I the one simple question : what be the MAC address for the new modem -lrb- which appear on a white sticker on the bottom of the modem , for those of you not familiar -rrb- . he do not ask what brand or give I the third degree about it be on the list of approve list . he provision it , it work , end of story . so yes , if you be a twc customer in North Carolina and want to replace you twc-supplied modem with one that work and that you own , this modem will do the job . 589 CableModem POS 5 the modem work great . vendor be quick to ship and I receive it on time , in great shape and ready to go . 397 CableModem POS 5 I buy this before Comcast install my new service , but I could not get it to work at the time of my self-activation . I put it aside for a few week and come back to it . after have Comcast 's " Ubee " brand for a few week , which cap at 44mbp -lrb- we be suppose to have a 50mb line -rrb- , I decide to try one night to just plug in the Motorola to see what would happen . it take a while , maybe 20 minute and 5 reset , before the modem finally download the firmware it be suppose to which allow the Comcast " self-activation " screen to appear . after this point it be smooth sailing , though it take 30 more minute for the Comcast activation to work . the best part ? Speedtest now run at a solid 54.78 mbp ! I have run speedtest probably 20 time over the last week and it have never move off that number . that be get my money 's worth and also not pay Comcast for a slower modem . 543 CableModem NEG 1 this amp do not work with the latest cable modem such as Motorola sb 6120 . the amplifier definitely boost the tv signal as I can verify that signal-to-noise ratio increase from around 32 db to 40 db . however , the amp seem to either block full bi-directional communication or filter out require frequency for the cable modem to make online connection to isp -lrb- in my case Comcast -rrb- . furthermore , the vendor 's -lrb- cabletvamps.com -rrb- 's support be a joke . when I ask why it be not work with my cable modem , the reply be a copy\/paste of some unrelated topic about the amp not support satellite tv and I should return the product . Main reason I purchase the booster be to split to both cable modem and tv without drop signal strength to the cable modem , but that be not possible with this junk . I be back to use a simple -3.5 db splitter that support upto 1,000 MHz Update ! - the CableTVAmps support finally reply : quote : `` the Motorola s2 be a passive return unit - these be not design to be use with Cable Modems as they will not support the signal . you will need a active return amplifier -lrb- the Motorola k4 be a 4-port unit -rrb- which will support a Cable Modem and any interactive service -lrb- OnDemand , etc. -rrb- that the Cable Company offer '' 779 CableModem POS 5 I can not tell you how many time I call my local cable tv provider -lrb- Comcast -rrb- to complain about the poor picture quality on my tv . I be unable to watch my brand new Sony flat screen hd tv due to pixelization and completely blank channel . it be happen every day . all Comcast would do be send a signal to the digital box to try to correct it . they even send a service man out to look at it . he check all the connection inside and out and tell I if the problem continue , to call . they be totally worthless . I be ready to cancel my cable tv subscription , when someone at work suggest a signal booster . so , I sign onto my favorite website in the world ! ... Amazon.com ... and find this wonderful little thing ! very simple to hook up outside where the cable wire feed into the house . it be like flip a switch . no more pixel across my screen and I be also able to pick up channel I do not have before ! it really do work . I have have it now for 2 week and have not have one problem with my tv . well worth the $ 52 I pay for it ! Motorola Signal Booster 4-port bda-s4 Cable Modem tv hdtv amplifier 241 CableModem POS 5 Have have the same modem for about 10 year and it finally start give I problem . talk to comcast and they say I should change it out and the loss connectivity issue would go away . as well as I get all the speed I be pay for on the internet . for once they where right . connection be simple and no issue along with my dowload speed doubling . my netflix stream alot better on my tv and with the 3 laptop go at the same time everything be run smoothly . I be be cheap not want to upgrade but it be well worth it . the fam be verry happy I break down and do it . Hope this help anyone out there think about the upgrade . 566 CableModem POS 5 the earlier review be right about this device . once properly set up , it run without a hitch , and we internet connection seem to be a bit faster than with the older modem it replace , which we have foolishly rent from Comcast for year . I do , however , have some trouble get it register with Comcast . I have read the review say that you just plug it in and fire up you browser to get the online Comcast registration screen , but that do not work for we -lrb- we never see that screen -rrb- . it take a couple of call to Comcast -- the first one to someone who have not a clue , and the second one to someone much more knowledgeable -- to get it register . once that be do , it have work without a hitch for about a week . 784 CableModem POS 5 this modem be easy to install. , at first I could not get it to hook up to the internet. , but with a little tweeking , -lrb- unpluging power cord -rrb- I get it to work . you must call you internet service to register it . work just fine . 279 CableModem POS 5 Got this for my Comcast service & it work great ! no problem with it at all and work great with the Belkin router that I buy too ! 278 CableModem POS 5 I have have this modem for about a month now . it work flawlessly . in fact it increase my speed from roughly 20mb\/s to 40mb\/s over cox . its a nice compact unit , and have a couple keyhole for wall\/shelf mount . 180 CableModem POS 5 it arrive shortly after order . the prong on the plug be a little bent , but I just get out the pliers and fix it . just plug everything in how comcast , or whoever , have theirs set up and you be almost there . the next time you try to log on to the internet , it will walk you through how to register it and then internet will be yours and you will no longer have to pay comcast they 7 dollar every month for a little box that you can install all by yourself . 349 CableModem POS 4 I purchase the modem think that the docsis 3.0 would help increase my speed ... it do not . other than that , the model work well . 586 CableModem NEU 3 I buy this because I be move to Comcast Internet , and I want a fast modem that would not give I any trouble . unfortunately , the first one keep power cycling when I get it hook up . I call Motorola tech support , who tell I that a low sigal to noise ratio be cause the power cycle . I call Comcast , and they tech come out and fix the low snr problem , but the modem keep power cylcing . he replace it with a Comcast modem , which work just fine . the replacement modem that I get work fine , but I be only rating this 3 star because of the hassle I have to go through get it to work . 294 CableModem POS 4 this modem work , mostly . it do not seem significantly faster than the old Motorola , though I be guess it would test faster . there be a diminish return for simple web surfing when the older generation of modem be already capable of load a page in few tenth of a second . download be probably faster , but I rarely pay attention to that anyway , since I have train myself to immediately switch to another task whenever I click on a download button . I be still get request from Windows 7 to connect to broadband via dial-up , so either I trigger something in win7 during the installation process , or it periodically think there be no cable modem . I just have to click the cancellation button a few time , which be annoying , but not a big deal . I have no major issue set up the modem with Comcast in Maryland , though it do take they a few try to get everything talk to everything else . the total time might have be 10-15 minute , vs. the 5 I have be hope for , so also no big deal . 985 CableModem POS 5 before I purchase this modem , I do some research . I be not techy and be worry about buy something I could not use with Comcast , my internet provider . I call Comcast and they tell I this particular Motorola model -lrb- any model over `` 5000 '' -- related , apparently , to model number -rrb- would work . I look at post on techy site . some user have report trouble with activate they modem with Comcast . I , fortunately , do not run into trouble . I connect the modem -lrb- it be very easy -rrb- . I call Comcast . I provide they with the serial number -- and the `` hfc MAC ID '' number . both of which be located on the box the MODEM come in . I be tell the `` MAC ID '' number be what Comcast principally use to activate the modem through they system . so far , so good . it be easy to set up and be work as expect . and I love not give extra money to Comcast because I no longer rent they modem and router . 290 CableModem POS 5 this be a great modem . nothing to do but hook it up , call you cable company to give they the hardware address and wait for they to imput the info . it connect in less than 5 minute . 253 CableModem POS 5 Easy to install and work great . ca not believe the improvement in the cable tv signal quality . 292 CableModem POS 5 I have have this modem for month now , and it have be great , no hiccup or anything , cant go wrong with this purchase . I see some folk that be say that it get extrememly hot , mine have be fine , obviously it need to breathe just like most electronics . 703 CableModem NEG 1 listen to the other one star review ! I think , `` sure , a few people get a bad unit that continually reset itself , but surely , Motorola have fix the issue by now . there be so many good review , I 'll buy it ! '' wrong ! heap of junk continually reset . my cable installation be brand new , include the main box in the back yard . Moto be worthless . 54 CableModem POS 5 I replace the rent Cisco dpc3010 with this model . I get the same download -lrb- 40 + mbp -rrb- and upload -lrb- 4 + mbp -rrb- speed as before . the MAC address change be simple , Charter Communications be able to facilitate it in a few minute while I be on the phone with they . the box say `` Comcast certify only '' , but I can attest that it work with Charter in San Luis Obispo County California . 237 CableModem POS 5 get a use Motorola dsl modem sb5100 but do not come with the power supply . get this replacement and it work perfectly , no problem what so ever , and it come with a unbitable that price . 175 CableModem POS 5 setup be hassle free with this cable modem . Modem have plenty of capacity to maximize my current speed from my cable provider with lot of room to grow when the cable provider upgrade they infrastructure in the near future . Easy interface with my wireless router . 928 CableModem POS 5 setup seem easy enough . call Comcast and feed they the mac address . the light go into action and I be up and run in no time . look like we enjoy higher internet speed with comcast -lrb- although they customer service be terrible -rrb- . glad to have this modem which support gigabit speed . 351 CableModem POS 5 this product be exactly as describe , it work perfectly with my Motorola Surfboard sb5101 . actually it be much more space-saving than the previous power supply I have for my modem . 743 CableModem POS 4 use this modem with Comcast . I do not even have to call they to activate it . I just use the self-activation website and be up and run in less than 5 minute . I get this to replace a sb6121 because I want 8 downstream channel , plus the sb6121 run too hot and I have to have a fan blow on it . I be on the blast 25\/4 tier and with the sb6121 I be get 36.5 mbp down and 6.5 mbp up with Power Boost . with the dpc3008 I be get 36.1 down and 5.6 up with Power Boost . Kind of disappointing . like with the dpc3000 and dpc3010 , the dpc3008 's diagnostic screen be gimp to only show you the signal level . no channel frequency , no uptime , and no log . if Motorola can show all this information in a read-only format , why can not cisco ? another disappointment . as long as the modem work it be not that big of a deal , but detailed diagnostic information can be very helpful if you really need it . temperature wise the dpc3008 run cooler than the sb6121 and do not need a fan blow on it , so I 'll stick with it for now . 526 CableModem POS 5 this work great . basically plug n play . Super fast ship and look good too . no complaint so far and I have be use it for about a month now . would not hesitate to buy from this merchant again . 901 CableModem NEG 1 I would not buy Zoom again ! we purchase this unit - start out ok , then six\/seven month later zoom push out a update through we internet provider , put the unit into vapor lock ! they customer service be really bad here - take 24 to 48 hour -lrb- m-f only -rrb- to get they to send you the e-form to fill out in order to get a rma # -lrb- so I can pay to ship it back to repair they screw up -rrb- , 2-4 day shipping , 5-10 day for repair , 2-4 day shipping -lrb- if they decide I do not do something to the unit -rrb- so three week later I can get internet back !! 157 CableModem POS 5 I absolutely love this modem . the lead 's be super cool and the design be awesome for how compact it be . I have mine in open air not surround by anything and this modem never heat up it and have stay at the same temp as it first start . speed be amazing also , this modem keep I either at my advertised rate without drop in speed or it even increase it to almost 2x as fast as what I pay for . so far I get this to work with charter high speed call they to activate it and once activate there have be no problem at all . overall for a great Modem to replace you old beat up docsis 2.0 modem and take advantage of the new speed I would highly recommend this modem for a great internet experience . \*\*\* Update 6\/15\/12 \*\*\* : it time for out with the old and in with the new ! Docsis 2.0 modem now will be speed cap since cable network be upgrade to docsis 3.0 . that be why you need this guy ! . not only have it give I up to double my speed but it also give I a constant internet speed . I still highly recommend it ! 862 CableModem POS 5 great unit . try several Motorola modem before and they never work properly . the zoom work immediately with Comcast , easy set-up and no problem . 625 CableModem POS 4 I pick this up from another retailer when the Motorola sb6121 give I problem the thing keep reset . a real pain when play on line game this one be fast and reliable . no problem whatsoever . a small footprint on my desk since I do not need a separate router as well . only hiccup be a standard setting that block against flood of datum attack with the high speed Comcast I get 30m download so it think someone be flood my computer with datum . a email to zoom and they give I the quick answer on what security set to uncheck 851 CableModem POS 5 this router\/modem work great . it be really easy to set up . the instruction say that I might have to call my internet provider -lrb- for I that be Comcast -rrb- , but the setup do everything automatically . it be ship very quickly , and be very well package . 20 CableModem POS 5 do this modem also a router for wi-fus ? , would appreciate some feedback , thinking of buy this item if it would do what I expect . 223 CableModem POS 5 require a call to comcast customer service for a serial number input . after that , it worked\/works extremely well ! ca not recommend this enough . 565 CableModem POS 4 Works well , box have wrong mac id so setup be delay . great modem tho . no complaint so far even tho refurbish 420 CableModem POS 5 while look for way to cut down my cable bill , I search around and find this modem . check the approve modem list , this be on there , order it up , few day later it be in my hot little hand . after a quick call to the cable provider -lrb- who need the MAC address -rrb- , it be up and online . I be use this with a Netgear WNR2000 that be flash with dd-wrt , rock solid with no issue so far . definitely one of the easier computer-related project I have do around the house this year : d 800 CableModem POS 5 I have Comcast -lrb- nee Adelphia -rrb- cable modem service . bought my own modem back in 2005 I believe , and have be use it since then . finally decide it be time for a upgrade , so purchase the sb6121 after a bit of research . no problem connect it . need to call Comcast support to get it activate : it take longer to find they number and navigate through the automate phone support than it do once the tech be on the line . once I be actually talk to someone , it be a 3 minute process : read she the MAC address , she put it in and reset the signal , and I be up and run . notice a definite jump in my download speed compare to the old modem . only con I would say be the fact that the status light on the front of this modem be not actually label ; they just show various symbol which you need to figure out . they be not that obscure , I would just prefer label . other than that , the modem be great . 523 CableModem POS 5 be run the sb6121 for a few week with a old e1000 router . I feel a little warm spot on top of the case , the rest of the box be cool , a little chunkier than the sb5100 , and full of perforation . have to call Comcast before the new modem start work : -lrb- Occupy Comcast after repower the sb6121 , it take longer to reconnect than the 5100 , then it work fine . the modem 's web-interface show that instead of one download frequency , now I have four , thanks to the Docsis 3 , although my download speed have not increase . url for the web interface be slightly different than the sb5100 , but if you start at the traditional 192.168.100.1 , you 'll get in . the web-interface webpage be very similar to the 5100 . slightly different light on the front panel . one day , I 'll look they up and see what they mean . -lrb- Update -- on my modem , the downstream light be blue , which mean the connection be use multiple downstream channel bond together , else the light would be green to indicate use a single downstream channel . the upstream light be green since my connection use only one upstream channel , but it would turn blue if the upstream bond multiple channel . whether you connection use single channel or multiple channel be determine automatically when the modem connect to the cable system . -rrb- I replace my 5100 because it be start to have trouble communicate ; long wait to connect , have to use process of elimination to determine the problem be the 5100 . my connection be stable again , but it be the same speed as before . take the router out of the system -- go straight from the sb6121 to a computer , I see a powerboost of 30 mbits\/sec for the first 15 seconds of download , and then 13 mbits\/sec for the duration . I think that be about what I get on the old modem , too . -lrb- with the e1000 router in line , the download speed be only 12 mbits\/sec and there be not any boost -- bottleneck be the router . -rrb- 832 CableModem POS 4 my prior modem be a DOCSIS 1.1 model from linksy which have a web base user interface point out in the ship installation Guide . I would have give this Motorola modem a perfect rating if the ship box also include info on how to access the modem 's user interface via a web browser . fortunately , on the motorola.com site I find a detailed pdf installation Guide with the web interface IP address that make up for the miss info . the web address be -lrb- ... -rrb- some people complain about the heat discharge by the modem but I do not think it be hot enough to cause any problem as long as the modem be keep in a well ventilate space . 905 CableModem POS 5 this cable modem work great with my Comcast internet . Comcast service technician complete the setup so I can not vouch for ease of setup , but unit have work flawlessy for several month . I have not need to reset the modem even once . 546 CableModem NEG 2 I could not get this modem to work . Comcast technician could not figure out what be wrong with it . I do not think this modem work for everyone . 322 CableModem POS 5 omg ! I love this modem . I be get faster connection then before . I have this connect to my wireless router and it rock ! I wish I have buy this sooner ! 99 CableModem NEU 3 I give all 5 star for this item attribute , but only 3 star in general rating and here be the reason why . I have 4 FIOS Cable box in my house and they be , of course , in different room and I be use a regular splitter for this . you can imagine how many cable I have and how far they be go . so hd picture be degrade on two of my tv - there be pixelation and sound be be lose . I go look for a good signal booster and find this one . I get it , install it and it be perfect - no more signal loss and picture and sound be like it be a direct cable connection . BUT , to my big disappointment on the two cable box that be connect to this booster I be no longer get the connection to my dvr , connection to all the Verizon FIOS service from the box get lose and I could not get any channel lineup . so I do further research and stumble upon this review : amazon.com\/review\/rk8zfk6zyl6jy\/ref=cm_cr_pr_viewpnt#rk8zfk6zyl6jy apparently for the Cable tv service to work you need a booster with `` active return Cable Modem boost '' , which be this one : Motorola Signal Booster 4-Port Cable Modem TV HDTV amplifier with active return Cable Modem boost but the bda-k4 \/ ra model sell for the exact same price as the bda-s4 , so I be return this one and get the one with active return Model Boost . I will try to review it after I get it and test it . 164 CableModem POS 5 this cable modem be exactly what I need . it support the fastest residential speed offer by Comcast -lrb- DOCSIS 3.0 -rrb- , and I have not have a single problem with it since I start use it . it be only about 30 dollar more than the cheapest cable modem I could find . I would definitely recommend this cable modem , and I would purchase again . 483 CableModem POS 5 this modem work right away on Comcast 's network . just have to go through the provision process and register over the phone . 866 CableModem POS 5 plug and play . speed improve compare to my old docsis 2 cable modem . no complaint at all so far . I recommend this product . 208 CableModem POS 5 I purchase this to take the place of a sb6120 that my grandson decide need to be hit against a wall . oh well . anyway , it appear to function the same as the 6120 . I do notice that on a few speed test I do go over 62mb . I never get over 59mb on the 6120 . now do that mean it be faster or better ? who know ! I know I do not know ! I have notice a uptick in the wireless network . I be run the modem through my latest generation Apple Wireless with my iMac hard wire via ethernet . I also use a extreme to extend the network as the speed drop on my wireless network in the front of the house . so the modem work well , do not seem to heat up , keep the signal , look nice , have pretty button , ok I be ramble ... ... ... ... look it work . if and when it act up I will update my review to indicate problem . 837 CableModem NEG 1 set up a new Comcast account , I have go through two attempt with Motorola modem . the first be the sb6020 , which be DOA -- would not even power up . send it back and decide to try the sb6121 , to see if they newer model perhaps have better quality control . I think I be go to have success -- the light come on -- but no luck . the first strike against this modem come when I call Comcast to try to do a `` self-install '' to save the service charge of the technician come out . in we new place , I know the previous tenant have use Comcast , so I be sure the house be already wire correctly . Comcast be unable to do a self-install over the phone for this modem , so a technician be send out . the Comcast technician , a nine-year veteran installer , spend over a hour fight with the sb6121 , try to get it to initialize . we wire it in directly , remove all splitter , etc. . . and it still refuse to recognize . keep cycling and drop service . I spend another hour on the phone with Motorola tech support , who be unable to help . finally , as a last resort , the Comcast technican plug in a similar Docsis 3.0 modem from he truck . the connection be up and work in seconds , with a stable signal and no drop service . of course , I be now fight with Comcast over the $ 99 service charge for the technician . all tell , this modem have cost I 3-4 hour of my life and $ 99 already ... and this be my second return of a Motorola modem to Amazon in less than 10 day . and I still need a modem . with the dubious quality of the current generation of Motorola modem , they have lose I as a customer for the forseeable future . if the next model be better , I 'll revisit the issue but for now , the aggravation and expense just be not worth it . 854 CableModem POS 5 the modem arrive quickly and be just as advertise , with the exception of a miss coax cable . it take quite a while for the Comcast system to establish a connection with the modem -lrb- the installer say this be typical of this modem -rrb- , but it be be work perfectly ever since connection be finally establish . 677 CableModem POS 5 product come in the original packaging and work like a charm out of the box . no issue at all to date -lrb- only be about a month -rrb- . I no longer have to pay the ridiculous Comcast fee and have better performance to boot . very satisfied . 806 CableModem NEG 1 just get this in the mail . horrible connection and super slow compare to the ARRIS I be rent from Comcast for $ 7\/mo . I be consider keep the rental and suck up the fee just to get decent internet . ca not even stream video from Youtube \/ etc without it buffer every 5 seconds . sad . 993 CableModem POS 5 I recently replace the Comcast provide 5120 with this 6121 , the set up on my side take about 3 minute , and it take about 15 when I call to update the MAC address with Comcast . in the last few week I have have no issue with this modem , the connectivity be rock solid , the speed be high and consistant , and I no longer have to pay the annoying rental fee each month . 911 CableModem POS 5 I have internet service thru Charter , and purchase this modem to replace the Charter rental unit . it be easy to install , and come with everything I need . 488 CableModem POS 5 install easy with a one time call to Comcast and have be work great . increase my download and upload speed by 30 % . 386 CableModem POS 5 I get this unit to replace the cable company 's device . this work better than the one they have I on and in 8 month it will have pay for it be self in the rental fee I be be charge . 528 CableModem POS 5 great equipment ; use since 3 month now and no trouble what so ever . my internet go up and down very randomly but I do not think it the problem of this equipment , I try with other modem too . there be different deal on amazon for the same item , make sure you choose the inexpensive one . 147 CableModem POS 5 all I have to do be to replace the old CableModem , hookup up the new surfboard , and call Comcast to give they the new MAC address , and within 5 minute the upgrade be complete . 459 CableModem NEU 3 bda-s4 boost only 12x 484095-001-00 Boost 32X Part of it because of the splitter . if you need better boost -lrb- and only use single tv -rrb- , choose 484095-001-00 . if you need splitter and do not need so much boost you can go with bda-s4 Wish BDA-S4 have more boost . maybe 20x . it will be great 387 CableModem POS 5 well my old DOCSIS 2 modem begin to loose speed and would disconnect frequently . it be a good 5 or more year old . so buy this and set it up with comcast real easy , call the service number say I want to give the mac address of my new modem and service be back up and run in a few min . now I be get increase speed , and no more trouble with comcast . unfortunaly the router will be the next thing to be replace as the router be limit my speed now . but this product do it be job and do it well with my comcast internet . 876 CableModem POS 5 I have Comcast xfinity . I disconnect my old modem , connect this modem , and then `` re-plugged '' my wireless router . a Comcast installation screen appear on my laptop when I open Explorer . you need you Comcast account number -lrb- on you bill -rrb- , I follow the step , and it work great . I do not need they , but I be keep the number on the bottom of the box . 637 CableModem NEU 3 I be unable to actually use the product , as it do not have a telephone jack in it , which be what I need accord to the cable company , in addition to the ethernet jack . I do have a problem with the seller , as there be no refund , and I be not aware of it at the time of my purchase . if I have read all the post regard the seller and he irate response , I would not have do business with he in the first place . Buyer beware . it come with a 90-day manufacturer 's warranty as refurbish and do not have a problem with that , and come complete with installation disc , usb cord and ac adapter . I relist back onto Amazon and sell it right away . 332 CableModem POS 5 I read all the posting on the Motorola sb6121 and decide to give it a shot . I be pleasantly surprise . I call my Comcast technical help and they get my MAC address instead of the S\/N id as state in some other post . within a minute I be online . unless there be something out there that be go to jump at I later , I believe this be a great product and worth the money . it work very well with my Medialink Wireless-N Router . 123 CableModem POS 5 I have always consider Cisco the gold standard for network hardware , but they gear have usually be out of my price range . I be excite when I see the price tag on this so go for it . so far I have be very happy with it be performance and reliability . very highly recommend . 91 CableModem POS 5 I recommend replace you comcast or other provider supply cable modem , with this linkys cm100 . Works perfect !! very happy and worth the money . 402 CableModem POS 4 the product arrive intact . setup be easy . just need to plug in the cable , call Comcast , and the whole thing start to work . I have be use the modem for 2 month . so far , there have not be any problem . the price at $ 140 be certainly a bit steep . I have not do any deep technical datum gathering yet . simple internet speed test indicate the modem can certainly support the specific speed I order via Comcast . the only drawback be Motorola do not offer any warranty on the device . so beware about this fact before make you purchase . 957 CableModem POS 5 this work great with Comcast . I be very pleased with the speed , performance and the easy installation . the size be just right . I hate big and bulky equipment . 794 CableModem POS 4 I be expect improvement in speed , but it do not happen . it be stay about the same 14-16 mb\/s . not sure it be modem 's or isp . do not need to reboot all the time like the old one . will see in the future . 954 CableModem POS 5 I move into a new home which have seven cable outlet in different room . one of the bedroom I turn into a office but the problem be that I only have one cable connection in the room . the connection do okay with either the cable modem or the hdtv but not with both connect . the cable modem would not connect with the tv connect to a splitter . I connect the amplifier and run one cable to the tv and the other to the cable modem . I cross my finger and plug it in ... now I have a great cable internet and hdtv signal , both from one cable connection . the only thing I have a problem with be the 13 day it take from the time I order until the time I receive the item , but that have nothing to do with the item itself . 572 CableModem POS 5 work like a charm right out of the box ! no fuss , no muss . I have purchase this to extend signal about 100 ' and because of the multiple output port , I hook up short coax cable to the closest tv and dvd recorder as well . Picture quality also improve a lot ! 260 CableModem POS 5 very good Modem Works Great , if for any reason , you have a very low upload speed after install , call you cable company to adjust they signal for work to the modem docsis 3.0 , -lrb- a lot of cable company still have they signal to docsis 2.0 -rrb- that just happen to I , but after my cable company do the adjustment the modem work perfect . 83 CableModem NEU 3 I just get this modem from Amazon . I buy it to replace my aging Linksys modem . I do a few speedtest.net check before I unhook the linksy and I be get 15.7 mbp down and 4.7 mbp upload . that be acceptable even though my neighbor with the same comcast internet as I have be get 33 down and 9 up with a comcast modem . I hook up this Motorola modem and I be sad to report now I be get 8mbp upload and 34mpb upload ! the upload go through the roof but I dont upload a ton of stuff the download go down by 50 % . I want it the other way around -lrb- like my neighbor have -rrb- . I may have to return this modem as this be not acceptable . 426 CableModem NEG 1 disappoint with Motorola for this one . the modem begin fail just after the one year warranty expire . I replace it with a Cisco . 304 CableModem POS 5 great product , double my download and upload speed . Easy installation , only problem be with comcast argue about MAC code since it be different from what they be use to . since I have have it no problem whatsoever . Easy to see and understand lead graphic display . I would highly recommend it for gamer who want the top speed that they can get from they provider . 791 CableModem POS 5 Works greatly with Comcast , just make sure install the driver firstly . the usb cable be not necessary . the package be easy to open and I love it . nothing fancy but everything work . 410 CableModem POS 5 Charter just bump we up to 30Mb and this require I get a DOCSIS 3.0 modem and it have be wonderful !! 425 CableModem POS 4 Easy to hook up and once you call Comcast to tell they you have a new modem , this work right away . have it for two week with no problem . 564 CableModem POS 4 I just love this super fast modem . its be a few month now since I get it and its totally dependable and super fast . its be work day and night with no problem since I receive it ... super fast with high response . 130 CableModem POS 5 have roadrunner turbo . North Carolina . Doc . 3 not available in my area , but will be implement by the end of the year . -lrb- hahah , sure . -rrb- anyways , I be get 10mb on average , while drop down to 2 or 4mb during peak hour . have a UBEE doc . 2.0 modem , and finally say , `` screw it '' and get this one . take 2 hour on the phone with roadrunner support for they to finally approve my MAC address . the tier 1 tech can not approve the modem to work . you will have to go to tier 2 or 3 . once roadrunner finally approve the modem , it work flawlessly . I be get 20 mb steady during peak hour , and upload have increase from 500k to 2mb . Modem run a bit hot , but that be it . 28 CableModem POS 5 I receive the package yesterday and have this modem work inside of 20 minute . I simply unhook my old modem and follow the step to hook this one up . I run the installation guide cd and when I be do it display the ` Mac '' address , tell I that Comcast will need it and direct I to call they for activation . after the usual 10 minute of they try to get I to NOT talk to a real person I finally get someone on the line who ask I for the Mac address and boom everything work perfectly . I then plug the Ethernet cable back into my wireless router and the three lap top , a couple of Roku 's , a Blu Ray player and the wireless printer all work great . I be not one to constantly check download speed but I be get some download interruption with the last modem so I want to replace it with a newer model . Time will tell but so far I be very pleased with this item and for the price it be a super deal . for my application this get 5 star Amazon be incredible but you need to be on you toe . I have this item in my cart and be ready to purchase it for $ 54.49 . somehow I delete it from my cart and run a new search and come up with this exact same item in a so-called environmentally safe box for $ 29.00 . there must be a catch . I have momentary buyer 's remorse when I be wait on the line with Comcast but absolutely not a issue . no catch and I save $ 25 . remember this be a 2.0 DOCSIS modem not the 3.0 high speed one . I do not pay Comcast for they high speed internet service and my research say I do not need the 3.0 for the level of service that I have with they . so for about $ 30 you can own you own cable modem , eliminate the monthly rental fee and pay this off in about three or four month . March 23rd update-i notice that the price have go up from $ 29 to $ 44.99 since I buy this -- now only $ 10 savings 379 CableModem POS 4 this be a inexpensive cable modem that get the job do reliably . I save money by use my own rather than rent one from Comcast . configuration be simple . the modem 's only flaw be that it have only a single Ethernet port . of course , you can plus a router into it , but it would be nice if it have a small router build in . 306 CableModem POS 5 great modem , come fast and be easy to install . I call up comcast and give they the MAC to provision it , but they say it would take up to three day . for instant satisfaction , I tweet that comcast customer service suck . a rep reply and ask to help . I direct message he with the account number and MAC , and the box be provision within minute . long story short , get the thing run within the first hour I have it and it be a perfect replacement for the crap smc gateway device Comcast usually require -lrb- and charge $ 7\/m for -rrb- . 987 CableModem POS 5 Comcast be my isp . this cable modem be on Comcast 's approve list for all residential speed tier but be sure to check for yourself before order any modem . I have Performance internet tier and get about 21.5 mbp download and 3.8 mbp upload accord to speedtest.net . previously , I be get about 11 mbp download and 1.8 mbp upload use a old Motorola sb4100 . I have not have any problem with the modem overheating . 166 CableModem POS 5 Modem be very easy to hook up . love the slim design and the fact that you can either lay it flat or stand it up . 527 CableModem POS 5 my first option be to buy a Arris WBM760A as part of a new setup to replace a unreliable surfboard sbg6850 but it be not be sell anywhere but ebay for more than I would like to pay . after receive the Ubee 3513 from Amazon , Comcast could not activate it and have try different method to activate it without success . I have lose hope and almost return the Ubee to Amazon until I come across someone on the internet mention that they have activate they modem by use Comcast 's activation page . I give it a try and presto ... activation success ! so if you be have difficulty as I be , try comcast.com\/activate so far , the cable modem have be great . there be no drop or reset . I also have a Motorola SBG6580 that constantly reset ... stay away from the sbg6580 as many have say of its problem ! Update : recently I find out why the ubee have trouble set up with Comcast when I request a technician to do a final check to see if my internet connection be good . when Comcast try to setup the ubee , they system do not expect a customer to own a ubee modem so it will not setup . now if you use the online setup , the modem will be setup but however as a Netgear modem . as a Netgear modem , there be no functional issue as it may have the same chipset as the ubee modem . this be the best way to set this modem up and then leave it that way . be careful if you have a Comcast tech set this modem up as a ubee , you will be charge the rental because Comcast detect ubee serial number as belong to Comcast . now I have a problem with Comcast to straighten out because the tech setup my ubee modem as a ubee modem instead of leave the modem as a Netgear modem . -lrb- see update below , maybe you can setup the ubee modem the right way by call Comcast ? -rrb- Update : in regard to Comcast modem rental charge ... my local Comcast store can not help with the rental charge . I call Comcast billing today to tell they that I own my ubee modem and that I be be charge the rental . all they do be ask for the modem serial number and mac address , and without further question correct the problem and refund my rental fee . Sweet ! we 'll see when my next bill arrive . 3-8-12 406 CableModem POS 5 great Modem and easy to hook up . just make sure that it be one of the approve router for you service that you be sue . then give they you MAC I.D. # and thenmake sure that you router if use one be reset to except information from this modem and you be all set . fast router . but if you be use Telephony on you computer this modem will not handle this service . it have the capability of be one of the fastest modem out there currently . 359 CableModem POS 5 buy this to replace my rent modem from comcast . all I do be plug it all in but then have to call comcast to make the change . it be pretty easy and it only take I about 30 min to get everything do . 38 CableModem POS 5 the Comcast people be very pleasant but could not get the modem to work . then , I use the following sequence -lrb- page 10 of the download manual -rrb- , and the modem start to work : configure tcp\/ip for Windows 7 1 . click Start and then click control panel . 2 . click Network and Internet to display the Network and Internet window . 3 . click Network and share Center to display the Network and share Center window . 4 . click Change adapter setting to display the lan or High-Speed Internet connection window . 5 . right-click the network connection for you network interface . 6 . Select Properties to display the local area connection Properties window . 7 . Select Internet Protocol Version 4 or 6 -lrb- tcp\/ipv4 or v6 -rrb- and click Properties to display the internet Protocol Properties window . 8 . Select Obtain a IP address automatically and obtain dn server address automatically . 9 . click ok to save the tcp\/ip setting and close the internet Protocol Version 4 -lrb- tcp\/ipv4 -rrb- Properties window . 10 . click Close to close the local area connection Properties window . 11 . close the remain window and exit the control panel . when you complete the tcp\/ip configuration , go to verify the IP Address for Windows 7 . the modem do not come with a cd or manual . 492 CableModem POS 5 I have be use it for 3 month and it work better than the modem comcast give I . speed be good thanks to the docsis 3 and it never need rebooting . thanks Amazon ! 799 CableModem POS 5 I would strongly recommend this modem . have go with this modem after not be happy with the more expensive Motorola SB6120 surfboard -lrb- Wireless be slow -rrb- . installation be quick , modem work excellent -lrb- with Comcast -rrb- and pair with my dir-825 xtreme n it put out fast wireless speed . I even get 54mbp when outside in the back yard of a fully brick home . 765 CableModem POS 5 I 'll make this quick and hope I be not jinx myself . this be the easiest thing I have do in deal with Comcast . I lease this ubee modem already through Comcast and want to just buy one instead . I originally buy the Motorola sb6121 . I be sure the modem be fine , but I have issue in get it work with the Comcast representative , ` course that be probably the main problem right there . anyway , I return it and buy this ubee -lrb- which be the exact model I have be lease -rrb- . I unplug they modem , plug mine in , go to comcast\/activate self install webpage and 10 minute or so later I be up a run with no issue -lrb- knock on wood -rrb- . I give Comcast they modem back today and hope I do not have to fuss at they billing department next . 297 CableModem POS 5 I mainly want to see if I could boost the signal to fix a issue with a down-line splitter . I be unable to get 2 tv to work with a in-house splitter , although they have work ok before . this leave I with connect only one tv , and switch it if I want to use the other tv -lrb- kitchen and basement -rrb- . I hook this new splitter up outside my house at the direct point where the cable line come to the house . this be split by the cable company into a 4-way splitter serve 4 jack in the house . as note , I have split the output from one of these jack to serve 2 other tv along with the one at the jack . this use to work , but stop and I could only go directly to one other tv . so this be a direct replacement for the exist outdoor 4 way splitter . I run a outdoor extension cord to hook up the power supply -lrb- which connect to the splitter via a short co-ax cable you need to supply yourself -rrb- . a green led let you know the splitter be power . I then reconnect the 4 line that run into the house and test everything out . I have no problem with the exist tv or the cable modem . not sure if picture quality be better or not , but it certainly be no worse . I then try out the 2 tv off the splitter and it now work ok , solve my problem . I have 2 analog tv with dta box and 4 hd tv with cable box , plus the cable modem , and everything be work well . I be go to look into run a cable line into the house so I can put the power supply in there , and also get some sort of plastic box to put the splitter in -lrb- like the telephone wiring -rrb- so it be a little more protect from the element . if all of you splitting happen inside the house , then you will not have this issue . 238 CableModem POS 5 so I need to say first off I buy this Modem for my new comcast service installation . before I have use the rental modem at several other place but note that my best internet speed be always with the Aris modem I have rent from comcast originally . I do the math and determine that in the long run buy my own modem be cheaper than a rental , plus I could take it with I when I move . -lrb- College student -rrb- so I have use speedtest to see that although I be pay for a 25mb\/s connection I be get nowhere near that speed with the previous qwest and comcast modem . I be not happy at all . Immediatley upon installation I run a speedtest and find that with my 25mb\/s connection I be get 40mb\/s download and 25mb\/s upload . this be AMAZING compare to the 12mb\/s download and 6mb\/s upload I be get with my previous modem . . now the bad , this guy be a pain to install . I do network management and computer repair and have install dozen of modems\/router setup . this guy just do not want to connect to comcast . I have initially have it install next to my tv then within a few hour want it directly hook to my router and desktop in the next room over . upon unplug it and run a line over to the next room I have hour worth of try everything from reset all of these device and troubleshooting . I eventually just leave it unplug for a hour or so as I be about to return the item as I fear it be defective . upon my return I replugg the entire setup into my network and it immediately connect to comcast as it should . I can not say this be optimum for any piece of hardware but I be happy with my new device and internet speed . I can stream movie and the such while play counterstrike with no drop in bandwidth or lag . 215 CableModem NEG 1 just do not help at all . make the picture worse , may have be defective so I send back . just get a good splitter from the local electronics store and it help much more than the signal booster . 870 CableModem NEG 1 just google for ` cisco dpc3008 customer support ' and you 'll see that one of the top hit be the comcast customer forum where hundred of people complain about the dpc3008 drop internet connection . because this modem be list on Comcast 's web site as a approve modem , I buy one 3 month ago . I have have nothing but trouble with it and to my surprise , discover that many other people be experience the same problem . under somewhat heavy load such as streaming a movie , the modem drop the internet connection . the only solution be to use a different modem . I replace the dpc3008 with a Motorola surfboard and have not have any problem . I would stay away from the dpc3008 , it do not work reliably . it 'll be the last Cisco product I ever purchase . 342 CableModem POS 5 I buy this for my cable modem and I notice a speed increase . the cable guy come by to replace my cable modem and even he notice a significant speed increase with he bandwidth measure device . this will save you lot of time when streaming and download thing off the internet , however , you might be spend more time on the internet since everything will be that much faster . 680 CableModem POS 4 I purchase this modem so I could save the $ 7 a month fee from Comcast . so far the modem seem to work just fine . should pay for itself in a year . 256 CableModem POS 5 Super fast ! Works great with Charter . have not disconnect so far . will not have to pay for modem rental ever again !!! a recommend buy ! 124 CableModem POS 5 after use a different cable modem for year , one ` highly ' recommend by the cable company and techy at a very popular Comuter , etc , store , I purchase the cm100 . I have not have one single problem as compare to five or more per week with the recommend one . the cm100 be very easy to install and understand . a miracle in itself !